The possible recovery of a white-spotted charr population in a small tributary of a river to Lake Biwa, following removal of previously stocked red-spotted masu salmon, was investigated by electrofishing. We captured 30 red-spotted masu salmon and two hybrids of these two species in 2014. Prior to the stocking of red-spotted masu salmon, the estimated number of white-spotted charr?≥?100 mm standard length (SL) in the tributary was more than 200 individuals in 2005, which had reduced to fewer than 30 individuals by 2014 when 30 red-spotted masu salmon plus two charr/masu salmon hybrids were captured. However, no red-spotted masu salmon were captured from 2015 to 2017, indicating the success of a red-spotted masu salmon removal program. The estimated number of white-spotted charr?≥?100 mm SL ranged from 25 to 91 individuals between 2015 and 2017, implying a great reduction of red-spotted masu. The estimated population size of the former increased further to 171–221 individuals in 2021, comparable to 2005. These results suggest that the white-spotted charr population declined due to stocking of red-spotted masu salmon, and recovered following removal of the latter.
This study investigated whether the consumption of a diet in which high-β-glucan barley replaced rice would reduce the visceral
fat area as well as the serum low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) in hypercholesterolemic
Japanese men. A randomized, double-blinded, placebo-controlled intervention study was conducted in 44 hypercholesterolemic
Japanese men with a body mass index (BMI) >22 kg/m2. The subjects were randomly assigned to groups consuming either rice (placebo group) or a mixture of rice and pearl barley
with a high β-glucan content (test group, 7.0 g β-glucan per day) for 12 weeks. Blood samples were taken, and CT scan obtained
before the trial and every four weeks during the trial. The pearl barley intake significantly reduced serum concentrations
of LDL-C (P = 0.041) and TC (P = 0.037) during the trial. Significant differences between the test and placebo groups were found for the visceral fat (P = 0.039), BMI (P = 0.015), and waist circumference (P = 0.011) at the end point. The consumption of pearl barley with a high β-glucan content reduces not only LDL-C but also visceral
fat area. 相似文献
A method for evaluating the umami taste intensity of green tea by a taste sensor system was established. Interference in the measurement from catechins was solved by removing the catechins from sample solutions with poly(vinylpolypyrrolidone). A 5.00 mM aqueous solution of glutamic acid monosodium salt was used as the standard solution. Sensor outputs were converted into EIT uma (estimated intensity of taste concerning umami) values. One unit on the EIT uma scale was defined as the amount of the sensor output corresponding to a difference in 1.2 times the concentration of the standard substance (glutamic acid monosodium salt). The umami taste intensity of green tea was classified into six grades on the EIT uma scale. Sensory tests proved that the EIT uma value had a high correlation to the human gustatory sense. 相似文献
To explore the mechanisms in the deposition and release of phosphorus (P) in the sediment of a shallow eutrophic lake using preserved samples, we investigated the vertical and temporal changes in P, manganese (Mn), sulfur (S), iron (Fe), aluminum (Al), calcium (Ca), and magnesium (Mg) in the sediment samples and the phosphate in the sediment pore water samples over a period of 6 years.
Materials and methods
The upper 15 cm of sediment from Lake Kasumigaura in Japan was collected monthly from 2003 to 2008 from the center of the lake. Sediment cores were divided into seven depth segments and were acid-digested for an elemental analysis via inductively coupled plasma atomic emission spectroscopy. Phosphate concentrations of the sediment pore water were determined using the molybdenum blue method. A multiple regression analysis was conducted by setting the P content as the response variable and Mn, S, Fe, Al, Ca, and Mg as explanatory variables.
Results and discussion
The results of the multiple regression analysis demonstrated that P co-precipitates with Fe and Al oxides and accumulates on the sediment surface. The vertical distributions of Mn and S suggest that Mn reduction occurs within the 0–1-cm-depth layer of the sediment and that iron sulfide is actively formed in the 6–10-cm-depth layer of the sediment. These findings imply that the layer in which ferric oxides are reduced to ferrous ions is present near the 1–6-cm-depth layer of the sediment. This layer corresponds to the layer in which the maximum phosphate concentration of the sediment pore water often occurred (the 2–6-cm-depth layer). These results indicate that vertical distributions of mineral elements are useful for assessing P dynamics in sediments.
Conclusions
The lake sediments record the dynamics of P in the sediment. Our analytical approach using long-term observation data demonstrated that the accumulation and release of P associated with a change in the redox state can be assessed based on the vertical distributions of mineral elements in the lake sediments.
Black lesions on shoots of European pear trees observed in an orchard in Yamagata Prefecture in May 2007 were suspected to
be caused by a bacterial pathogen. The surface of the colonies isolated on a high sucrose medium did not have the crater morphology
that is characteristic of E. amylovora bvs. 1–3, and a specific DNA fragment was amplified from the isolates in the PCR using the EprpoD primer set. The partial
sequences of the 16S rRNA gene placed the isolates in the genus Erwinia. The isolates differed serologically from E. amylovora biovars and E. pyrifoliae in an Ouchterlony double-diffusion test although their bacterial properties suggested that they are closely related to E. amylovora biovars and E. pyrifoliae. In a DNA–DNA hybridization test, the relatedness between the isolates and E. amylovora biovars or E. pyrifoliae did not exceed 70% level, indicating that they are independent species. Thus, the isolates belongs to the genus Erwnia but are not E. amylovra or E. pyrifoliae. After succulent pear shoots were injected with bacterial suspensions (109, 108, 107 and 106 cfu/ml) of the isolates, lesions formed with 109 and 108 cfu/ml, but the disease incidence with 108 cfu/ml was much lower than with E. amylovora and E. pyrifoliae. Virulence of the present isolates is thus thought to be very weak. On the basis of these results, we consider that this
is a new shoot disease of European pear. In the 2007 season, all affected trees were pulled out after harvest. No symptoms
have been observed in field surveys since the fruitlet season in 2007. 相似文献
Colloidal haze reduces beer quality considerably. Four haze samples were analyzed by two-dimensional gel electrophoresis (2DE) in order to identify haze-active proteins. Several protein spots were observed in all of the four haze samples. Using mass spectrometry analysis followed by a database search identified these spots as barley dimeric alpha-amylase inhibitor (BDAI-1), CMb component of tetrameric alpha-amylase inhibitor (CMb) and trypsin inhibitor CMe precursor (CMe). These proteins were considered to be haze-active. Since haze-active proteins are adsorbed by silica gel in the beer filtration process, we eluted proteins adsorbed onto silica gel (PAS) and identified their species. These major PAS were identified as protein Z4, protein Z7 and trypsin/amylase inhibitor pUP13 (TAI), rather than BDAI-1, CMb and CMe. Furthermore, we analyzed proline compositions in the beer proteins, PAS and the haze proteins. Consequently, we found that the proline compositions of PAS were higher (ca. 20 mol%) than those in the beer proteins (ca. 10 mol%), although those of the haze-active proteins such as BDAI-1, CMb and CMe were 6.6–8.7 mol%. Our results suggest that BDAI-1, CMb and CMe are not predominant haze-active proteins, but growth factors of beer colloidal haze. 相似文献
We examined the in vitro fermentation characteristics and in situ dry matter (DM) and crude protein (CP) degradability of tamarind kernel powder extract residue (TKPER), a by‐product of polysaccharides thickener processing. Two types of TKPER (I and II), of which the CP and neutral detergent fiber organic matter basis contents (%) were 41.4 and 42.0 and 1.4 and 0.5, respectively, were compared with dry heat soybean (SB), soybean meal (SBM) and dry soybean curd residue (SBCR). The TKPERs had significantly lower in vitro gas production compared to the other products at each observation time (P < 0.05). The in vitro DM and CP digestibility (%) of TKPER I and II were 67.7 and 64.9, and 64.5 and 58.0, respectively, significantly lower than those of SB and SBM (P < 0.05). We used four wethers (55.6 ± 4.6 kg) with ruminal cannulas to investigate the in situ degradability of TKPER I, SB, SBM and SBCR. At the ruminal outflow rate of 0.05/h, the effective degradability (%) values of the DM and CP of TKPER I were 64.1 and 49.7, respectively, which were similar to those of SBM. In conclusion, TKPER had high CP and exhibited in situ degradability similar to that of SBM, suggesting that TKPER could be used as a protein source feed. 相似文献
Insulin‐like factor 3 (INSL3) is essential for fetal testis descent, and has been implicated in the testicular and sperm functions in adult males; however, similar functions in domestic ruminants remain largely unknown. This study investigated the functional INSL3 hormone‐receptor system in adult ruminant testes and spermatozoa, and explored its potential to diagnose the fertility of sires. Testes and spermatozoa were obtained from fertile bulls, rams and he‐goats, whereas subfertile testes and spermatozoa were obtained only from bulls. As expected, INSL3 was visualized in Leydig cells, while we clearly demonstrated that the functional receptor, relaxin family peptide receptor 2 (RXFP2), enabling INSL3 to bind was identified in testicular germ cells and in the sperm equatorial segment of bulls, rams and he‐goats. In comparison to fertile bulls, the percentage of INSL3‐ and RXFP2‐expressing cells and their expression levels per cell were significantly reduced in the testes of subfertile bulls. In addition, the population of INSL3‐binding spermatozoa was also significantly reduced in the semen of subfertile bulls. These results provide evidence for a functional INSL3 hormone‐receptor system operating in ruminant testes and spermatozoa, and its potential to predict subfertility in sires. 相似文献
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